Strain engineered composite semiconductor substrates and methods of forming same

1. A method of fabricating a semiconductor substrate, comprising: forming a strained donor structure by forming a III-nitride material on a first substrate with a desired lattice strain and a Ga-face on a first surface of the III-nitride material and an N-face on a second surface of the III-nitride material; selecting an attachment surface, wherein the attachment surface is the first surface to form an N-polar composite substrate or the second surface to form a Ga-polar composite substrate; forming a weakened zone in the strained donor structure at a predetermined depth to define a strained seed layer between the attachment surface and the weakened zone and a residual strained donor structure between the weakened zone and a surface opposite the attachment surface; bonding a support substrate to the attachment surface of the III-nitride material; separating the residual strained donor structure from the strained seed layer at the weakened zone to form a strained composite substrate comprising the support substrate and the strained seed layer; epitaxially growing at least one additional layer of semiconductor material on the strained seed layer of the strained composite substrate to deposit a device structure; and selecting the desired lattice strain and a resulting strained lattice parameter of the III-nitride material and a composition of the at least one additional layer of semiconductor material and causing a reduction in a difference between the strained lattice parameter of the III-nitride material of the strained seed layer and an equilibrium lattice parameter of the at least one additional layer of semiconductor material.

2. The method of claim 1 , wherein forming the strained donor structure further comprises forming the III-nitride material to comprise Ga-polar III-nitride material on a growth substrate.

3. The method of claim 1 , wherein forming the strained donor structure further comprises: forming the III-nitride material to comprise Ga-polar III-nitride material on a growth substrate; bonding a carrier substrate to the first surface; and removing the growth substrate to expose the second surface of the III-nitride material with the N-face.

4. The method of claim 1 , wherein forming the III-nitride material on the first substrate with the desired lattice strain comprises selecting the first substrate to have a CTE different from a CTE of the III-nitride material such that, after a growth cycle and a cool down, the III-nitride material at room temperature is under a strain relative to the III-nitride material in a relaxed state at room temperature.

5. The method of claim 4 , wherein selecting the first substrate comprises selecting the first substrate to comprise a material selected from the group consisting of Si, SiC, GaAs, and AlAs.

6. The method of claim 1 , wherein forming the III-nitride material on the first substrate with the desired lattice strain further comprises forming at least one buffer layer between the first substrate and the III-nitride material, wherein an average lattice parameter of the at least one buffer layer is different from an equilibrium lattice parameter of the III-nitride material.

7. The method of claim 6 , wherein the at least one buffer layer is selected from the group consisting of AlGaInN, ZnO, HfN, and ScN.

8. The method of claim 1 , wherein forming the III-nitride material on the first substrate with the desired lattice strain further comprises doping the III-nitride material with a dopant and modifying a lattice parameter of the III-nitride material.

9. The method of claim 8 , wherein the dopant is selected from the group consisting of Si, Ge, Sn, Mg, Be, Zn and Cd.

10. The method of claim 1 , further comprising re-using the residual strained donor structure to form an additional strained composite substrate by repeating the acts of forming the weakened zone, bonding the support substrate, and separating the strained donor structure on the residual strained donor structure.

11. The method of claim 1 , wherein the desired lattice strain is a tensile strain.

12. The method of claim 1 , wherein the desired lattice strain is a compressive strain.

13. The method of claim 1 , wherein epitaxially growing the at least one additional layer of semiconductor material on the strained seed layer of the strained composite substrate to deposit the device structure further comprises maintaining a thickness of the at least one additional layer of semiconductor material below a critical thickness of the at least one additional layer of semiconductor material and preserving strain within the at least one additional layer of semiconductor material.

14. A method of fabricating a semiconductor structure, comprising: forming a strained donor structure, comprising: forming a III-nitride material on a growth substrate with a desired lattice strain and a Ga-face on a first surface of the III-nitride material; selecting the desired lattice strain and reducing lattice mismatch between the III-nitride material and at least one additional layer of semiconductor material of a device structure to be subsequently deposited on a strained seed layer comprising a portion of the III-nitride material; bonding a carrier substrate to the first surface while at least substantially maintaining the desired lattice strain in the III-nitride material; and removing the growth substrate to expose a second surface of the III-nitride material with an N-face; forming a weakened zone in the strained donor structure at a predetermined depth to define the strained seed layer between the second surface and the weakened zone and a residual strained donor structure between the weakened zone and the first surface; bonding a support substrate to the second surface of the III-nitride material while at least substantially maintaining the desired lattice strain in the III-nitride material; separating the strained donor structure from the strained seed layer at the weakened zone to form a strained composite substrate comprising the support substrate and the strained seed layer having the desired lattice strain; and epitaxially growing the at least one additional layer of semiconductor material on the strained seed layer of the strained composite substrate and forming the device structure; selecting a composition of the at least one additional layer of semiconductor material and a strained lattice parameter of the strained seed layer such that a difference between the strained lattice parameter of the strained seed layer and an equilibrium lattice parameter of the at least one additional layer of semiconductor material is reduced relative to a difference between an equilibrium lattice parameter of the seed layer and the equilibrium lattice parameter of the at least one additional layer of semiconductor material.

15. The method of claim 14 , wherein forming the III-nitride material on the growth substrate with the desired lattice strain comprises selecting the growth substrate to have a CTE different from a CTE of the III-nitride material such that, after a growth cycle and a cool down, the III-nitride material at room temperature is placed under a strain relative to the III-nitride material in a relaxed state at room temperature.

16. The method of claim 15 , wherein selecting the growth substrate comprises selecting the first substrate to comprise a material selected from the group consisting of Si, SiC, GaAs, and AlAs.

17. The method of claim 14 , wherein forming the III-nitride material on the growth substrate with the desired lattice strain further comprises forming at least one buffer layer between the growth substrate and the III-nitride material, wherein an average lattice parameter of the at least one buffer layer is different from an equilibrium lattice parameter of the III-nitride material.

18. The method of claim 17 , wherein the at least one buffer layer is selected from the group consisting of AlGaInN, ZnO, HfN, and ScN.

19. The method of claim 14 , wherein forming the III-nitride material on the growth substrate with the desired lattice strain further comprises doping the III-nitride material with a dopant and modifying a lattice parameter of the III-nitride material.

20. The method of claim 19 , wherein the dopant is selected from the group consisting of Si, Ge, Sn, Mg, Be, Zn and Cd.

21. The method of claim 14 , further comprising re-using the residual strained donor structure to form an additional strained composite substrate by repeating the acts of forming the weakened zone, bonding the support substrate, and separating the strained donor structure on the residual strained donor structure.

22. The method of claim 14 , wherein the desired lattice strain is a tensile strain.

23. The method of claim 14 , wherein the desired lattice strain is a compressive strain.

24. The method of claim 14 , wherein epitaxially growing the at least one additional layer of semiconductor material on the strained seed layer of the strained composite substrate and forming the device structure further comprises maintaining a thickness of the at least one additional layer of semiconductor material below a critical thickness of the at least one additional layer of semiconductor material and preserving strain within the at least one additional layer of semiconductor material.

25. A semiconductor structure, comprising: a support substrate; a strained GaN seed layer disposed on the support substrate, the strained GaN seed layer being in a state of tensile strain and having a selected strained lattice parameter; and a device structure including at least one epitaxial layer of InGaN on the strained GaN seed layer.

26. The semiconductor structure of claim 25 , wherein the strained GaN seed layer has a Ga-face polarity on a surface of the strained GaN seed layer adjacent the layer of InGaN.

27. The semiconductor structure of claim 25 , wherein the strained GaN seed layer has an N-face polarity on a surface of the strained GaN seed layer adjacent the layer of InGaN.

28. The semiconductor structure of claim 25 , wherein the at least one epitaxial layer of InGaN is in a strained state and has a thickness below a critical thickness of the at least one epitaxial layer of InGaN.

29. A semiconductor device, comprising: a strained composite substrate comprising: a support substrate; and a strained GaN seed layer disposed on the support substrate, the strained GaN seed layer being in a state of tensile strain and having a selected strained lattice parameter; and semiconductor device layers disposed on the strained GaN seed layer to form at least one electronic element, at least one photonic element, or a combination thereof, the semiconductor device layers including an epitaxial layer of InGaN on the strained GaN seed layer.

30. The semiconductor device of claim 29 , wherein the strained GaN seed layer has a Ga-face polarity on a surface of the strained GaN seed layer adjacent the epitaxial layer of InGaN.

31. The semiconductor device of claim 29 , wherein the strained GaN seed layer has an N-face polarity on a surface of the strained GaN seed layer adjacent the epitaxial layer of InGaN.

32. The semiconductor device of claim 29 , wherein the epitaxial layer of InGaN is in a strained state and has a thickness below a critical thickness of the epitaxial layer of InGaN.